Poswillo claimed that the disorder's frequent occurrence on one side of the face led to suggestion of interference with vascular supply and focal hemorrhage in the developing first and second branchial arch
Cusps of non-symphysial teeth in premaxillary internal series, forming a very concave arch in ventral view; 1 or 2 maxillary teeth; premaxillary external series 3 to 6 pentacuspid teeth; premaxillary internal series 4 or 5 pentacuspid teeth; first branchial arch
with 18 (7 + 11) to 23 (10 + 13) gill-rakers; two humeral brown blotches vertically elongated: first with upper portion large, followed by a post-humeral blotch diffuse and inconspicuous
Five new species of genus Astyanax Baird & Girard, 1854 from Rio Iguacu, Parana, Brazil (Ostariophysi, Characiformes, Characidae)/ Cinco novas especies do genero Astyanax Baird & Girard, 1854 do Rio Iguacu, Parana, Brasil (Ostariophysi, Characiformes, Characidae)
Distinguished from all other congeners by the combination of the following features: anterior portion of trunk slightly wider than deep, jaws short, snout blunt, tip of anal fin rounded in male, caudal fin elliptical to acuminate in male, pelvic-fin tip reaching the anterior portion of the anal-fin base in male, dorsal-fin origin posterior to anal-fin base, dorsal-fin rays 5-7, anal-fin rays 9-11, frontal squamation S-patterned, contact organs absent, frontal scales arranged circularly, canal preopercular short and opened, longitudinal series of scales 29-32, gill rakers of first branchial arch
1 + 7, oblique rows of red dots on flank in male, transverse black bar through the chin, and no black spot on dorsal portion of caudal-fin.
7) The etiology of the frequently associated ossicular chain anomalies maybe traced to an error in the development of the second branchial arch
prior to the fourth month of intrauterine life.
Management of congenital fourth branchial arch
anomalies: A review and analysis of published cases.
Description: Dorsal rays IX, 20 (18-19, see Table II); anal rays II,12 (II,13); all dorsal and anal soft rays branched except first, last dorsal and anal rays branched to base; pectoral rays 18 (17-18, see Table II); upper and lowermost pairs unbranched; pelvic rays I,5; branched caudal rays 15; scales in longitudinal series 63/64 (51-63); tubed lateral line scales 48/42 (33-46); scales below lateral line to origin of anal fin 21 (20-21); scales above lateral line to middle of dorsal fin base 5; gill rakers on first branchial arch
6 + 12 (5-6 + 11-12).
In our present findings, of the additional slip in the clavicular origin of sternocleidomastoid muscle may be due to abnormal splitting in the mesoderm of post-sixth branchial arch
There is also a possible difference in the number of gill rakers on the first branchial arch
During the post-flexion stage, eight branchial spines are observed in the lower branch of the first branchial arch
, increasing during pre-juvenile development until 14 at the beginning of the juvenile stage.
Approximately 95% of these anomalies are derived from the second branchial arch
and are incomplete; they often present within the first 2 decades of life.
Postulated factors include disturbance of the interactions of growth factors,2 teratogenic drugs like meclizine,7 trauma late in pregnancy and local ischaemia and amniotic bands causing pressure on the first branchial arch
The upper teeth are curved towards the middle of the pharynx, but the lower teeth project at right angles to the surface of the branchial arch
, across the flow of water.